Interesting piece in the New York Times about why movie trailers almost always feature male voices. Here's some excerpts from "Why Men Always Tell You to See Movies."
The question has been pondered by mystics through the ages, but in the sanctuary of cinema the voice of a sonorous, authoritative, fear-inspiring yet sometimes relatable presence is, invariably, that of a man. Consider the trailer and the omniscient, disembodied voice that introduces moviegoers to a fictional world.
...Do moviegoers want to hear female voices? Research indicates that our brains are wired to prefer theirs to male ones; that’s the reason robotic voices, like those in GPS devices, tend to be female. (This probably has an evolutionary explanation: fetuses in the womb, identifying with their caretaker, can distinguish their mother’s voice from others, a study published in the journal Psychological Science found.) When it comes to credibility, however, research into the perceived believability of a voice — an important quality for the omniscient narrator of a trailer, as well as the spokesman or -woman for any product, which is the function a trailer serves — tells a different story.
“On average both males and females trust male voices more,” said Clifford Nass, a professor of communications at Stanford, noting some gender disparity exists in that women don’t distrust female voices as much as men distrust them. In one study conducted at Stanford two versions of the same video of a woman were presented to subjects: one had the low frequencies of the woman’s voice increased and the high frequencies reduced, the other vice versa. Consistently subjects perceived the deep voice to be smarter, more authoritative and more trustworthy.
My wife and I have noticed how true this is in relating with our dog, Serena.
A low voice seemingly is interpreted by her as a growl, which gets Serena's attention when we want her to obey a command; a high voice gets her tail wagging, maybe because it sounds akin to the excited "yipping" of dogs when they happily greet each other (we hear coyotes doing this in our rural neighborhood).